HELP! I need legal advice regarding paternity and divorce!?

I gave birth to a baby on March 15, 2007. I was legally married to my soon to be ex, but he is not the father of the baby. In the hospital, I was told that in the state of Michigan, the husband has to be on the birth certificate, even if he isn't the biological father. I want to have my husband removed from the birth certificate, and have no obligations in regards to child support, and then proceed with the divorce proceedings. I don't know where to start and I've contacted various agencies to find out and I keep getting the runaround. Do I establish paternity first? Or file for divorce first? If the baby's biological father won't submit to a paternity test, what are my options?? It's a big mess, I know. But my husband and I weren't together when I conceived with my ex-boyfriend. Now, the ex-bf is saying he won't have to pay child support because he's not on the birth certificate and he isn't responsible for anything to do with our son! I don't have alot of money for an attorney!